/*

 *  kacpimon - Kernel ACPI Event Monitor

 *

 *  Monitors kernel ACPI events from multiple interfaces and reports them

 *  to the console.

 *

 *  Inspired by (and in some cases blatantly lifted from) Vojtech Pavlik's

 *  evtest.c, Zhang Rui's acpi_genl, and Alexey Kuznetsov's libnetlink.

 *

 *  Copyright (C) 2008, Ted Felix (www.tedfelix.com)

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 *  (tabs at 4)

 */

/* system */

#include <stdio.h>

#include <unistd.h>

#include <fcntl.h>

#include <sys/select.h>

#include <string.h>

#include <errno.h>

#include <malloc.h>

/* local */

#include "libnetlink.h"

#include "genetlink.h"

#include "acpi_genetlink.h"

#include "acpi_ids.h"

#include "connection_list.h"

#include "input_layer.h"

#include "netlink.h"

#include "kacpimon.h"

/* ??? Isn't this in a system header someplace? */

#define max(a, b)  (((a)>(b))?(a):(b))

/*********************************************************************/

/* Exit flag that can be set by any of the functions to cause the */

/* program to exit.  */

int exitflag = 0;

/****************************************************************

 *  Old /proc/acpi/event interface

 ****************************************************************/

static void process_proc(int fd)

{

	const int buffsize = 1024;

	char buffer[buffsize];

	ssize_t nbytes;

	for (;;)

	{

		nbytes = read(fd, buffer, buffsize - 1);

		/* ??? Do we need to worry about partial messages? */

		/* If there are no data to read, bail. */

		if (nbytes <= 0)

			break;

		/* Ensure we have a zero terminator */

		buffer[nbytes] = 0;

		printf("/proc/acpi/event: %s", buffer);

	}

}

// ---------------------------------------------------------------

static void open_proc(void)

{

	char *filename = "/proc/acpi/event";

	int fd;

	struct connection c;

	fd = open(filename, O_RDONLY | O_NONBLOCK);

	if (fd >= 0)

	{

		printf("%s opened successfully\n", filename);

		/* Add a connection to the list. */

		c.fd = fd;

		c.process = process_proc;

		add_connection(&c);

	}

	else

	{

		int errno2 = errno;

		printf("open for %s: %s (%d)\n", 

			filename, strerror(errno2), errno2);

		if (errno2 == EACCES)

			printf("  (try running as root)\n");

		if (errno2 == ENOENT)

			printf("  (ACPI proc filesystem may not be present)\n");

		if (errno2 == EBUSY)

			printf("  (ACPI proc filesystem is in use.  "

				"You might need to kill acpid.)\n");

	}

}

/****************************************************************

 *  Main Program Functions

 ****************************************************************/

static void monitor(void)

{

	while (exitflag == 0)

	{

		fd_set readfds;

		int nready;

		int i;

		/* It's going to get clobbered, so use a copy. */

		readfds = *get_fdset();

		/* Wait on data. */

		nready = select(get_highestfd() + 1, &readfds, NULL, NULL, NULL);

		/* If something goes wrong, bail. */

		if (nready <= 0)

			break;

		/* For each connection */

		for (i = 0; i <= get_number_of_connections(); ++i)

		{

			int fd;

			struct connection *p;

			p = get_connection(i);

			/* If this connection is invalid, bail. */

			if (!p)

				break;

			/* Get the file descriptor */

			fd = p -> fd;

			/* If this file descriptor has data waiting, */

			if (FD_ISSET(fd, &readfds))

			{

				p->process(fd);

			}

		}

	}

}

// ---------------------------------------------------------------

static void close_all(void)

{

	int i = 0;

	/* For each connection */

	for (i = 0; i <= get_number_of_connections(); ++i)

	{

		struct connection *p;

		p = get_connection(i);

		/* If this connection is invalid, try the next. */

		if (p == 0)

			continue;

		close(p -> fd);

	}

}

// ---------------------------------------------------------------

int main(void)

{

	printf("Kernel ACPI Event Monitor...\n");

	open_proc();

	open_input();

	open_netlink();

	printf("Press Escape to exit, or Ctrl-C if that doesn't work.\n");

	monitor();

	printf("Closing files...\n");

	close_all();

	printf("Goodbye\n");

	return 0;

}